Development and validation of spectrophotometric method for estimation of anti-asthmatic drug doxofylline in bulk and pharmaceutical formulation

A simple, sensitive and accurate UV spectrophotometric method has been developed for the determination of an anti-asthmatic drug, doxofylline, in raw material and in tablets. The drug showed maximum absorption at 272 nm in water. Beer's law was obeyed in the concentration range 5-50 mu g mL(-1) of drug with an apparent molar absorptivity and Sandell sensitivity of 6.2 x 10(3) L.mol(-1)cm(-1) and 0.0363 mu g cm(-2)/0.001A, respectively. The limits of detection and quantification were calculated to be 0.9623 and 2.9161 mu g mL(-1), respectively. The method was successfully applied to the determination of doxofylline in tablets. Results were validated statistically as per ICH guidelines. It was found that the excipients present in the commercial formulation did not interfere with the method.